Property, Plant, and Capitalized Software Property Plant and Equipment Table (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Land and improvements	$ 310us-gaap_LandAndLandImprovements	$ 318us-gaap_LandAndLandImprovements
Buildings and improvements	2,295us-gaap_BuildingsAndImprovementsGross	2,051us-gaap_BuildingsAndImprovementsGross
Computer equipment	1,693us-gaap_MachineryAndEquipmentGross	1,519us-gaap_MachineryAndEquipmentGross
Furniture and fixtures	675us-gaap_FurnitureAndFixturesGross	564us-gaap_FurnitureAndFixturesGross
Less accumulated depreciation	(1,982)	(1,760)
Property and equipment, net	2,991	2,692
Capitalized software	2,399	2,233
Less accumulated amortization	(972)	(915)
Capitalized software, net	1,427us-gaap_CapitalizedComputerSoftwareNet	1,318us-gaap_CapitalizedComputerSoftwareNet
Total property, equipment and capitalized software, net	$ 4,418us-gaap_PropertyPlantAndEquipmentNet	$ 4,010us-gaap_PropertyPlantAndEquipmentNet

Property, Plant, and Equipment Excluding Capitalized Computer Software, Net

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- Definition

Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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For each balance sheet presented, the amount of accumulated amortization for capitalized computer software costs.

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Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

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The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

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- Definition

Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

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Amount before accumulated deprecation and depletion of real estate held for productive use and additions or improvements to real estate held for productive use, examples include, but are not limited to, walkways, driveways, fences, and parking lots. Excludes land held for sale.

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Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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The cumulative amount of depreciation (related to capitalized assets classified as property, plant and equipment not otherwise defined in the taxonomy) that has been recognized in the income statement.

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